Michaelis-Menten Tool

Enzymes accelerate the rates of biochemical reactions. One of the most common schemes for describing enzyme kinetics involving a single substrate is the Michaelis-Menten scheme.

This interactive tool will help you understand Michaelis-Menten kinetics and observe the Michaelis-Menten equation at work.

${ Equation:~~~~V = {{\color{#729fcf}{k_{cat}} \color{red}{[E]_t}[S]} \over {[S]\ +\ \color{#8ae234}{K_M}}}~~~~Where~~~~\color{#8ae234}{K_M} = {{\color{#866EF2}{k_{-1}}\ +\ \color{#729fcf}{k_2}} \over {\color{#F2963C}{k_1}}} }$

k₁	k_-1	[E]_tin M, where “M” is molar	k₂ = k_cat in sec-1	K_Min M

In this model:

k_cat measures the number of substrate molecules "turned over" per enzyme molecule in one second. The k_catis also considered the "turnover number."

[E]_tmeasures the total enzyme concentration.

K_Mis the Michaelis constant, which is the substrate concentration at which the velocity is half of maximum velocity.

Use the sliders to change concentrations of k_cat, [E]_t, and K_M.

The resulting graph shows reaction velocity, V, as a function of substrate concentration [S].

Maximal velocity, V_max , is approached asymptotically. The Michaelis constant, K_Mis the substrate concentration yielding a velocity of V_max/2.